Directionality or directivity is the microphone's sensitivity or speaker behavior depending on the angle at which the sound is incident or emitted. It is not the same for all frequencies and is represented by the polar diagram.
Directivity and coverage angle are inversely related. Many loudspeakers are designed to distribute sound over large areas, and therefore have a wide coverage angle and a low directivity. The coverage angle is defined as the angle between the points where the sound pressure level is 6 dB below the sound pressure level on the speaker's axis.
Some loudspeakers have different polar patterns in the horizontal and vertical planes (floor speakers, for example), and other loudspeakers are symmetrical about the speaker's axis and therefore have identical polar patterns in both planes (ceiling speakers).
